This invention is related in general to ice axes, and more particularly to an ax which incorporates several traditional snow tools in one.
Over the years there have been proposed a large number of survival tools for campers, hikers, military personnel and others who want a relatively compact and lightweight multifunctional implement for use under circumstances where there is not access to all of the different tools needed to perform various tasks. In general, the tool should be lightweight yet have high structural strength to withstand rugged use. Furthermore, the tool should be adaptable to such uses with a minimum amount of simple assembly or adjustment.
The ice ax is one of the most versatile and important pieces of mountaineering equipment. Without it, safe alpine travel is restricted to easy scrambles. An ice ax, and skill in its use, allows you to venture onto all forms of snow and ice, enjoying a greater variety of mountain landscapes during more seasons of the year.
The modern ice ax is an inherently simple tool with many uses. Below the snow line, it is used as a walking cane and to help brake going downhill. But its main role is in snow and ice travel, where it provides balance or a point of security to prevent a fall and serves as a means to stop a fall. The design is often a trade-off between features that make the tool better for specific purposes. A long ax may be suitable for cross-country travel and scrambling, where it is used as a cane and to provide security in low-angle climbing. However, a shorter ax is more useful for the steeper slopes encountered in alpine climbing. Weight is another consideration; some very light axes are not designed to withstand the demands of general mountaineering.
In the past, backcountry travelers have used many different tools including the ice axe, snow saw and snow shovel to aid them in their excursions. The ice axe, among other functions, serves as an anchor, a walking stick and a means for self-arrest. Modern ice axes are composed of three main parts: shaft, head and spike.
Usually, the shaft is a hollow oval tube about 2-4 feet in length, with a maximum width of 1.25 inches and is made of chromalloy steel or tempered aluminum. At the upper end of the shaft is the head made of xe2x85x9 inch chromalloy steel having at its one end a pick about 5 inches long curving slightly downward with saw-like teeth on its underside. On the other end of the head is the adze which is formed as a flattened isoceles triangle about 1.5 inches on each side. The adze, is either welded at one end to the rest of the head or integrated into a single piece, and structured so its position is perpendicular to the shaft of the axe. Finally, one finds the spike, at the lower end of the shaft. It is xe2x85x9 inch thick, a 1 inch wide flat piece of chromalloy steel or aluminum tapering to a point that protrudes 2 inches beyond the lower end of the shaft. It is held in the shaft by means of a hard rubber bushing and fixed expansion pins.
Mountaineers are extremely conscious of the weight and bulk of gear that they carry because it represents added effort and encumbrance in climbing. Therefore, the need to carry an extra shafted tool such as a shovel must be weighed against its encumbrance. There may be no way to rescue an avalanche victim or dig an emergency snow shelter (snow cave) without a shovel. This invention provides a small lightweight solution to this problem.
The snow shovel is a fundamental piece of equipment for the winter montaineer, and every member of a winter party should carry one. The shovel is used to excavate climbers from avalanche debris, dig emergency shelters, prepare tent platforms, and clear climbing routes. In choosing a shovel, a climber is torn between the heavy, bulky grain scoop, ideal for moving large amounts of loose snow quickly but less useful for avalanche debris or snow caves, and the compact folding or sectional shovel, convenient to carry and therefore less likely to be left at home. A snow shovel has also become an essential tool for backcountry travel. It is used for excavating an avalanche victim, building a snow shelter, digging a snow pit, and as a deadman anchor. The shovel blade is roughly one foot square, made of either tempered aluminum or plastic. The shaft is usually a 1 inch hollow circular aluminum tube, sometimes collapsible, with a D- or T-shaped plastic handle. This shovel is small enough to carry full time and to use inside a snow cave. It is strong, can hold a significant amount of snow, and is stable to grip and use.
Another tool that is less frequently carried in the backcountry, but just as important as any other, is the snow saw. It is used to perform a Rutschblock test (a snowpack stability test), and is an effective tool for cutting snow blocks for a shelter. A typical snow saw made of xe2x85x9 inch tempered aluminum, would be 1-2 inches wide and 18-24 inches long with an L-shaped handle. The problem with most snow saws is that the depth of the cut is limited to the length of the blade. This is especially true in hard packed snow or ice.
Mountaineers trying to move safely through avalanche country need information on the ability of the snow to bond and sensitivity of the snowpack to forces that might cause it to avalanche. One can test for snow stability by using the Rutschblock test, for example, described below and of special relevance for the subject invention. This test is considered a particularly good indicator of the likelihood that a slope will slide. The test puts stress by a person on skis or on a snowboard on the top of a block or column of snow, whose width is about the length of a ski or snowboard, that has been excavated on three sides of a rectangular snow block. Clean vertical sides of the snow block should be made to a depth of about three feet which is readily achieved with the device of this invention, but achieved with great difficulty when a conventional short handled ice saw is used. The back wall of the block is cut free of the slope. A person on skis or snowboard steps onto the center of the block from the slope above. If the block supports the skier, that person then stresses the block with a series of jumps, leaping up with both skis. The amount of stress required to cause the block to fail at a weak layer is an indication of the relative stability of the slope. The device of this invention has been tested in this manner and shown to be able to cut the snow and/or ice to a much greater depth, and with greater ease, due to the length of the handle than can be done with a conventional ice saw.
Of course, the need for the reduction of weight in survival tools has been addressed by others as has the need to integrate one or another tool with the basic ice ax. In the prior art one finds several relevant inventions worthy of mention. Morgan in U.S. Pat. No. 5,345,635 (1994) discloses an ice ax shovel attachment thereby avoiding the need to carry an extra shafted tool which must be weighed against its encumbrance. However, there is a small problem in that the means for attachment are somewhat complicated. In an environment where a shovel is needed, any simplication of attachment is indeed a significant improvement. Patents have also been granted for modifications of ice ax heads: in 1998 to Brainerd U.S. Pat. No. 5,768,727, and in 1999 to Brainerd et al in U.S. Pat. No. 5,937,466. Smith in U.S. Pat. No. 4,727,609 (1988) discloses a multi-functional survival tool embodying a shaft, a tool head having a shovel blade portion which in turn consists of ax blade and hammer portions. In addition, the hollow shaft has slots therein for receiving a hunter""s bow and a removable knife blade. This is not for use in a mountaineering environment. Shandel in U.S. Pat. No. 5,297,306 (1994) discloses a multipurpose outdoor tool being an ax having an elongated socket along the top of the ax blade for insertion of a tang of a detachable implement such as a spade blade, a pick point, a saw blade, a grub hoe blade, a combination hoe and rake blade, or any of various other implements.
Thus, it is an object of the subject invention to optimize the utility of the well tried ice ax with its pick and adze by minimization of weight and maximization of its utility in an ice and snow survival mode.
It is another objective to embody therein an ice saw using the shaft (handle) of the ice ax to contain an ice saw providing the ability to cut into ice and snow more deeply by using the length of the shaft of a conventional ice ax as a far longer handle than the normal short handle of the conventional ice saw.
It is a further objective to integrate the spike of the ice ax with the ice saw so that it becomes a reversible tool with either the spike or the saw exposed as needed.
It is yet another object to provide holes therein the body of the ice ax head and even the adze while maintaining their necessary strength in order to reduce overall weight.
It is also an object to provide shock absorbing upper spacers at the top of the shaft to be fixed to the shank of the ice ax head.
It is another object to provide lower spacers to the bottom of the ice ax shaft to secure a means for removing and replacing the combination spike and ice saw from the shaft.
It is an object to do the above with a minimum amount of simple assembly or adjustment.
It is a further object to do this in a tool at a low cost of fabricating the individual components and of assembling them into the completed tool.
A multipurpose ice ax for backcountry travel comprising: a head having a pick at its first end and an adze at its second end; a hollow shaft having holes therein its upper end to internally receive a shank of the head said shank having matching holes therein, said shaft having holes therein its lower end for receiving a combined reversible spike saw having matching holes therein; upper spacers connecting said shank of the head within said upper shaft for reducing the shock of said shank against said shaft when the force of the head impacts snow and ice; lower spacers having holes therein for connecting and rigidly fixing said spike saw within said lower shaft; means for reversing said spike saw to expose said spike or said saw as necessary; and a shovel blade having a blade portion and a pipe like portion having holes therein carried separately from the integrated multipurpose ice ax and attachable to said lower shaft by means of a shovel fastener inserted through matching holes of said shaft and said pipe like portion while said spike saw is attached to said shaft.